The present state of the art in concrete research has demonstrated the benefits of utilizing byproduct industrial waste materials as partial cement replacements. The byproduct industrial waste material, also known as mineral admixtures, such as fly ash, slag, and silica fume, can be used as partial cement replacements to change the characteristics and increase the performance of concrete. The use of byproduct material conserves energy, and has additional environmental benefits because of the reduced production and use of cement which can be associated with high carbon dioxide emissions. Byproduct materials, such as fly ash, slag, and silica fume, however, are not always readily available in all areas of the world. These materials are often imported, which increases the cost of concrete production.
In the production of titanium metal, waste byproducts are produced that are generally expensive to store and dispose of, and that are typically not useful. A need exists for an economical and environmentally friendly technique for putting such byproducts to good use.
Producing pigment grade titanium dioxide (TiO2) involves chemical processes. Two processes for the manufacture of TiO2 pigment are the sulphate process and the chloride process. In the sulphate process, titanium slag or ilmenite (FeTiO3) is digested with strong sulphuric acid to solubilize titanium, which is later hydrolyzed and precipitated to form TiO2. In the chloride process, rutile (crystalline polymorphic TiO2) or high purity ilmenite is chlorinated to form gaseous titanium tetrachloride (TiCl4), which is purified and oxidized to form TiO2. Both processes generate large amounts of industrial waste byproducts that must be stored and disposed of properly, involving significant costs and energy use. A need exists for an economical and environmentally friendly technique for putting such byproducts to good use.
Furthermore, a need exists for economical and environmentally friendly cement replacements and methods of making concrete compositions.